Forcing all mute changes to go through set_mute() makes it easier to
check where the muted field is changed, and it also allows us to have
only one place where notifications for changed mute are sent.
Since some devices can be chatty with regards to how often they return
from poll(), this adds a PA_UNLIKELY() to all the the rewind_requested
checks in our sink modules to make the general case (no rewind was
requested) the fast path.
When a rewind is requested on a sink input, the request parameters are
stored in the pa_sink_input struct. The parameters are reset during
rewind processing, and if the sink decides to ignore the rewind
request due to being suspended, stale parameters are left in
pa_sink_input. It's particularly problematic if the rewrite_bytes
parameter is left at -1, because that will prevent all future rewind
processing on that sink input. So, in order to avoid stale parameters,
every rewind request needs to be processed, even if the sink is
suspended.
Reported-by: Uoti Urpala
Some sink flags are really just a product of what callbacks
are set on the device. We still enforce a degree of sanity
that the flags match the callbacks set, but we also set the
flags automatically in our callback setter functions to
help ensure that a) people use them and b) flags & callbacks
are kept in sync.
This is not currently useful but future commits will make further
changes concerning automatic setting of flags and event delivery
that makes this structure necessary.
I hope this is enough, since the removal of the other pa_rtpoll_install()
calls deemed Linux good enough, but said nothing about Solaris, but since
the function is gone there is little more to do.
Lennart wrote,
>
> Hmm, yes. As it seems I broke the build for non-dbus builds.
Well, you also broke the solaris module between 0.9.15-test8 and 0.9.15.
Have you considered release candidates?
Patch follows. It would be nice if API changes could be made without
breaking things when the effort to avoid that is trivial.
Finn
On Wed, 4 Mar 2009, Lennart Poettering wrote:
[snip]
> > This patch disables link map/library versioning unless ld is GNU ld.
> > Another approach for solaris would be to use that linker's -M option,
> > but I couldn't make that work (due to undefined mainloop, browse and
> > simple symbols when linking pacat. I can post the errors if anyone is
> > intested.)
>
> The linking in PA is a bit weird since we have a cyclic dependency
> between libpulse and libpulsecommon which however is not explicit.
Could that affect the pacat link somehow?
What are the implications for client apps that link with the non-versioned
libraries I've been building on solaris?
[snip]
> > struct userdata {
> > pa_core *core;
> > @@ -87,15 +92,24 @@ struct userdata {
> >
> > pa_memchunk memchunk;
> >
> > - unsigned int page_size;
> > -
> > uint32_t frame_size;
> > - uint32_t buffer_size;
> > - unsigned int written_bytes, read_bytes;
> > + int32_t buffer_size;
> > + volatile uint64_t written_bytes, read_bytes;
> > + pa_mutex *written_bytes_lock;
>
> Hmm, we generally try do do things without locking in PA. This smells as
> if it was solvable using atomic ints as well.
>
> Actually, looking at this again I get the impression these mutex are
> completely unnecessary here. All functions that lock these mutexes are
> called from the IO thread so no locking should be nessary.
>
> Please don't use volatile here. I am pretty sure it is a misuse. Also
> see http://kernel.org/doc/Documentation/volatile-considered-harmful.txt
> which applies here too I think.
OK, I've removed the locks. For some reason I thought that the get_latency
function was called from two different threads.
> > +static void sink_set_volume(pa_sink *s) {
> > + struct userdata *u;
> > + audio_info_t info;
> > +
> > + pa_assert_se(u = s->userdata);
> > +
> > + if (u->fd >= 0) {
> > + AUDIO_INITINFO(&info);
> > +
> > + info.play.gain = pa_cvolume_avg(&s->virtual_volume) * AUDIO_MAX_GAIN / PA_VOLUME_NORM;
> > + assert(info.play.gain <= AUDIO_MAX_GAIN);
>
> I'd prefer if you'd use pa_cvolume_max here instead of pa_cvolume_avg()
> because this makes the volume independant of the balance.
>
> > - info.play.error = 0;
> > + info.play.gain = pa_cvolume_avg(&s->virtual_volume) * AUDIO_MAX_GAIN / PA_VOLUME_NORM;
> > + assert(info.play.gain <= AUDIO_MAX_GAIN);
>
> Same here. (i.e. for the source)
Done and done.
> > + if (u->sink->thread_info.rewind_requested)
> > + pa_sink_process_rewind(u->sink, 0);
>
> This is correct.
>
> >
> > err = ioctl(u->fd, AUDIO_GETINFO, &info);
> > pa_assert(err >= 0);
>
> Hmm, if at all this should be pa_assert_se(), not pa_assert() (so that
> it is not defined away by -DNDEBUG). However I'd prefer if the error
> would be could correctly. (I see that this code is not yours, but
> still...)
Done.
> > + case EINTR:
> > + break;
>
> I think you should simply try again in this case...
Done.
> > + case EAGAIN:
> > + u->buffer_size = u->buffer_size * 18 / 25;
> > + u->buffer_size -= u->buffer_size % u->frame_size;
> > + u->buffer_size = PA_MAX(u->buffer_size, (int32_t)MIN_BUFFER_SIZE);
> > + pa_sink_set_max_request(u->sink, u->buffer_size);
> > + pa_log("EAGAIN. Buffer size is now %u bytes (%llu buffered)", u->buffer_size, buffered_bytes);
> > + break;
>
> Hmm, care to explain this?
EAGAIN happens when the user requests a buffer size that is too large for
the STREAMS layer to accept. We end up looping with EAGAIN every time we
try to write out the rest of the buffer, which burns enough CPU time to
trip the CPU limit.
So, I reduce the buffer size with each EAGAIN. This gets us reasonably
close to the largest usable buffer size. (Perhaps there's a better way to
determine what that limit is, but I don't know how.)
> > +
> > + pa_rtpoll_set_timer_absolute(u->rtpoll, xtime0 + pa_bytes_to_usec(buffered_bytes / 2, &u->sink->sample_spec));
> > + } else {
> > + pa_rtpoll_set_timer_disabled(u->rtpoll);
> > }
>
> Hmm, you schedule audio via timers? Is that a good idea?
Perhaps not. I won't know until I test on more hardware.
But, given that we have rt priority and high resolution timers on solaris,
I think it is OK in theory...
The reason I used a timer was to minimise CPU usage and avoid the CPU
limit. Recall that getting woken up by poll is not an option for playback
unfortunately. We can arrange for a signal when the FD becomes writable,
but that throws out the whole buffer size concept, which acts to reduce
latency.
> That really only makes sense if you have to deal with large buffers and
> support rewinding.
I've implemented rewind support, but I'm still not sure that I have
understood the concept; I take it that we "rewind" (from the point-of-view
of the renderer, not the sink) so that some rendered but as yet unplayed
portion of the memblock/buffers can then be rendered again?
> Please keep in mind that the system clock and the sound card clock
> deviate. If you use the system timers to do PCM scheduling ou might need
> a pa_smoother object that is able to estimate the deviation for you.
Actually, in an earlier version I did use a smoother (after reading about
that in the wiki). But because of the non-monotonic sample counter (bug?)
I decided that it probably wasn't worth the added complexity so I removed
it. I'll put the smoother back if I can figure out the problem with the
sample counter.
>
> > + u->frame_size = pa_frame_size(&ss);
> >
> > - if ((fd = open(p = pa_modargs_get_value(ma, "device", DEFAULT_DEVICE), mode | O_NONBLOCK)) < 0)
> > + u->buffer_size = 16384;
>
> It would appear more appropriate to me if the buffer size is adjusted by
> the sample spec used.
Done.
> One last thing: it would probably be a good idea to allocate a pa_card
> object and attach the sink and the source to it.
It is possible to open /dev/audio twice by loading the solaris module
twice -- once for the sink (passing record=0) and once for source (passing
playback=0), thus giving seperate threads/LWPs for source and sink. It
might be misleading to allocate two cards in that situation?
> Right now pa_cards are mostly useful for switching profiles but even if
> you do not allow switching profiles on-the-fly it is of some value to
> find out via the cards object which source belongs to which sink.
>
> Otherwise I am happy!
>
> Thanks for your patch! I'd be thankful if you could fix the issues
> pointed out and prepare another patch on top of current git!
No problem. Patch follows. It also includes a portability fix for
pa_realpath and a fix for a bug in the pa_signal_new() error path that
causes signal data be freed if you attempt to register the same signal
twice.
> I hope I answered all your questions,
Your answers were very helpful, thanks.
Finn
>
> Lennart
>
>
Hi All,
This patch fixes the solaris audio device source and sink, and fixes some
portability issues that break the build on solaris. Questions and comments
welcomed.
I've tested this patch only with OpenSolaris Express snv 103. Eventually I
hope to be able to test a few older releases and older hardware (though it
is hard to say whether there is much interest in those).
This is my first brush with pulseaudio and so I read the wiki docs and
some of the source code but I'm still unsure of a few things. In
particular I'm wondering about rewind processing, corking and what (if
anything) the module needs for those. I'm also unclear on the implications
of thread_info.buffer_size, .fragment_size and .max_request, and whether
my code is correct or not.
This patch disables link map/library versioning unless ld is GNU ld.
Another approach for solaris would be to use that linker's -M option, but
I couldn't make that work (due to undefined mainloop, browse and simple
symbols when linking pacat. I can post the errors if anyone is intested.)
Thanks,
Finn Thain
pa_logXXX(__FILE__":
and replace them by
pa_logXXX("
git-svn-id: file:///home/lennart/svn/public/pulseaudio/trunk@1272 fefdeb5f-60dc-0310-8127-8f9354f1896f
for > 2 channels, so we'll have to rely on the user.
git-svn-id: file:///home/lennart/svn/public/pulseaudio/trunk@889 fefdeb5f-60dc-0310-8127-8f9354f1896f
to be written. Also, the sample counter can magically go backwards sometimes,
causing havoc with our buffer handling.
git-svn-id: file:///home/lennart/svn/public/pulseaudio/trunk@762 fefdeb5f-60dc-0310-8127-8f9354f1896f
